Watch Grey's Anatomy – Season 5 Episode 17: I Will Follow You Into the Dark
Cast: Kevin McKidd , Kim Raver , Jason George , Ellen Pompeo , Chandra Wilson , James Pickens Jr. , Caterina Scorsone , Camilla Luddington , Chris Carmack , Anthony Hill
Directors: Shonda Rhimes
Watch Grey's Anatomy – S5E17
Episode Overview
Derek decides to quit after learning that more of his patients have died than survived; Izzie's interns make an unsettling discovery about "Patient X."
